#!/usr/bin/perl

#	Check the stack usage of functions
#
#	Copyright Joern Engel <joern@lazybastard.org>
#	Inspired by Linus Torvalds
#	Original idea maybe from Keith Owens
#	s390 port and big speedup by Arnd Bergmann <arnd@bergmann-dalldorf.de>
#	Mips port by Juan Quintela <quintela@mandrakesoft.com>
#	IA64 port via Andreas Dilger
#	Arm port by Holger Schurig
#	sh64 port by Paul Mundt
#	Random bits by Matt Mackall <mpm@selenic.com>
#	M68k port by Geert Uytterhoeven and Andreas Schwab
#	AArch64, PARISC ports by Kyle McMartin
#	sparc port by Martin Habets <errandir_news@mph.eclipse.co.uk>
#
#	Usage:
#	objdump -d vmlinux | scripts/checkstack.pl [arch]
#
#	TODO :	Port to all architectures (one regex per arch)

use strict;

# check for arch
#
# $re is used for two matches:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the size of the stack growth
#
# $dre is similar, but for dynamic stack redutions:
# $& (whole re) matches the complete objdump line with the stack growth
# $1 (first bracket) matches the dynamic amount of the stack growth
#
# use anything else and feel the pain ;)
my (@stack, $re, $dre, $x, $xs, $funcre);
{
    my $arch = shift;
    if ($arch eq "") {
        $arch = `uname -m`;
        chomp($arch);
    }

    $x	= "[0-9a-f]";	# hex character
    $xs	= "[0-9a-f ]";	# hex character or space
    $funcre = qr/^$x* <(.*)>:$/;
    if ($arch eq 'aarch64') {
        #ffffffc0006325cc:       a9bb7bfd        stp     x29, x30, [sp,#-80]!
        $re = qr/^.*stp.*sp,\#-([0-9]{1,8})\]\!/o;
    } elsif ($arch eq 'arm') {
        #c0008ffc:	e24dd064	sub	sp, sp, #100	; 0x64
        $re = qr/.*sub.*sp, sp, #(([0-9]{2}|[3-9])[0-9]{2})/o;
    } elsif ($arch =~ /^x86(_64)?$/ || $arch =~ /^i[3456]86$/) {
        #c0105234:       81 ec ac 05 00 00       sub    $0x5ac,%esp
        # or
        #    2f60:    48 81 ec e8 05 00 00       sub    $0x5e8,%rsp
        $re = qr/^.*[as][du][db]    \$(0x$x{1,8}),\%(e|r)sp$/o;
        $dre = qr/^.*[as][du][db]    (%.*),\%(e|r)sp$/o;
    } elsif ($arch eq 'ia64') {
        #e0000000044011fc:       01 0f fc 8c     adds r12=-384,r12
        $re = qr/.*adds.*r12=-(([0-9]{2}|[3-9])[0-9]{2}),r12/o;
    } elsif ($arch eq 'm68k') {
        #    2b6c:       4e56 fb70       linkw %fp,#-1168
        #  1df770:       defc ffe4       addaw #-28,%sp
        $re = qr/.*(?:linkw %fp,|addaw )#-([0-9]{1,4})(?:,%sp)?$/o;
    } elsif ($arch eq 'metag') {
        #400026fc:       40 00 00 82     ADD       A0StP,A0StP,#0x8
        $re = qr/.*ADD.*A0StP,A0StP,\#(0x$x{1,8})/o;
        $funcre = qr/^$x* <[^\$](.*)>:$/;
    } elsif ($arch eq 'mips64') {
        #8800402c:       67bdfff0        daddiu  sp,sp,-16
        $re = qr/.*daddiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
    } elsif ($arch eq 'mips') {
        #88003254:       27bdffe0        addiu   sp,sp,-32
        $re = qr/.*addiu.*sp,sp,-(([0-9]{2}|[3-9])[0-9]{2})/o;
    } elsif ($arch eq 'parisc' || $arch eq 'parisc64') {
        $re = qr/.*ldo ($x{1,8})\(sp\),sp/o;
    } elsif ($arch eq 'ppc') {
        #c00029f4:       94 21 ff 30     stwu    r1,-208(r1)
        $re = qr/.*stwu.*r1,-($x{1,8})\(r1\)/o;
    } elsif ($arch eq 'ppc64') {
        #XXX
        $re = qr/.*stdu.*r1,-($x{1,8})\(r1\)/o;
    } elsif ($arch eq 'powerpc') {
        $re = qr/.*st[dw]u.*r1,-($x{1,8})\(r1\)/o;
    } elsif ($arch =~ /^s390x?$/) {
        #   11160:       a7 fb ff 60             aghi   %r15,-160
        # or
        #  100092:	 e3 f0 ff c8 ff 71	 lay	 %r15,-56(%r15)
        $re = qr/.*(?:lay|ag?hi).*\%r15,-(([0-9]{2}|[3-9])[0-9]{2})
            (?:\(\%r15\))?$/ox;
    } elsif ($arch =~ /^sh64$/) {
        #XXX: we only check for the immediate case presently,
        #     though we will want to check for the movi/sub
        #     pair for larger users. -- PFM.
        #a00048e0:       d4fc40f0        addi.l  r15,-240,r15
        $re = qr/.*addi\.l.*r15,-(([0-9]{2}|[3-9])[0-9]{2}),r15/o;
    } elsif ($arch =~ /^blackfin$/) {
        #   0:   00 e8 38 01     LINK 0x4e0;
        $re = qr/.*[[:space:]]LINK[[:space:]]*(0x$x{1,8})/o;
    } elsif ($arch eq 'sparc' || $arch eq 'sparc64') {
        # f0019d10:       9d e3 bf 90     save  %sp, -112, %sp
        $re = qr/.*save.*%sp, -(([0-9]{2}|[3-9])[0-9]{2}), %sp/o;
    } else {
        print("wrong or unknown architecture \"$arch\"\n");
        exit
    }
}

#
# main()
#
my ($func, $file, $lastslash);

while (my $line = <STDIN>) {
    if ($line =~ m/$funcre/) {
        $func = $1;
    }
    elsif ($line =~ m/(.*):\s*file format/) {
        $file = $1;
        $file =~ s/\.ko//;
        $lastslash = rindex($file, "/");
        if ($lastslash != -1) {
            $file = substr($file, $lastslash + 1);
        }
    }
    elsif ($line =~ m/$re/) {
        my $size = $1;
        $size = hex($size) if ($size =~ /^0x/);

        if ($size > 0xf0000000) {
            $size = - $size;
            $size += 0x80000000;
            $size += 0x80000000;
        }
        next if ($size > 0x10000000);

        next if $line !~ m/^($xs*)/;
        my $addr = $1;
        $addr =~ s/ /0/g;
        $addr = "0x$addr";

        my $intro = "$addr $func [$file]:";
        my $padlen = 56 - length($intro);
        while ($padlen > 0) {
            $intro .= '	';
            $padlen -= 8;
        }
        next if ($size < 100);
        push @stack, "$intro$size\n";
    }
    elsif (defined $dre && $line =~ m/$dre/) {
        my $size = "Dynamic ($1)";

        next if $line !~ m/^($xs*)/;
        my $addr = $1;
        $addr =~ s/ /0/g;
        $addr = "0x$addr";

        my $intro = "$addr $func [$file]:";
        my $padlen = 56 - length($intro);
        while ($padlen > 0) {
            $intro .= '	';
            $padlen -= 8;
        }
        push @stack, "$intro$size\n";
    }
}

# Sort output by size (last field)
print sort { ($b =~ /:\t*(\d+)$/)[0] <=> ($a =~ /:\t*(\d+)$/)[0] } @stack;
